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Hot Weather Is Becoming More Common in More Places

From VOA LearningEnglish, this is Science in the News. I’m FaithLapidus.

And I'm BobDoughty. Today we talkabouthotweather in the UnitedStates and around the world. We alsotellyouabout the bestways to prevent and treatproblemscaused by extremeheat.

Floods, storms and othernaturaleventskillthousands of peopleeveryyear. Sodoesextremeheat. In fact, expertssayheatmay be nature’s deadliestkiller. Severalhotdays that followeachother are considered a heatwave. Expertssayheatwavesoftenbecomedangerouswhen the nighttimetemperaturedoes not dropmuch from the highestdaytimetemperature. This putsgreatpressure on the humanbody.

Over the pastmonth, the northeasternUnitedStates has been veryhot. Amtrak, the passengerrailroadservice, announced on July 18th that it was reducing the speed at which its trainstravel in the Northeast. The reason: extremeheat. Amtraksaid it made the decisionafter the temperatureinsidesometraintracksroseabove 48.9 degreesCelsius.

The hotweatheralsoreached the northernstate of Alaska. Alaska is known for coldweather in winter and mildsummers. In June, the town of Talkeetna, 200 kilometersnorth of Anchorage, hit an all-timehigh of 35.5 degreesCelsius. The NationalWeatherServicesays the averagetemperaturethere for this time of year is 17.8 degrees.

Along the borderwithMexico, additionalofficershave been deployed out of concern for peopleseeking to enter the UnitedStates. There was a report that at leastthreepeoplewhoattempted to cross the borderillegallyintoArizonawerefounddead in June. Officialssaytheymostlikelydiedbecause of the extremeheat.

On the otherside of the world, somepeopledied in Shanghai, Chinaduring the city’s hottestJuly in 140 years. The temperature in severalChineseprovinceshitover 39 degreesCelsius. Onetelevisionstationshowedimages of a piece of meatcooking in the street to demonstrate the extremeheat. The ChinaMeteorologicalAdministrationwarnedpeople to limitoutdooractivities.

In Australia, record-settingheatfueledbushfiresacrossTasmaniaearlier this year. The highesttemperature, 49.6, was recorded in Moomba, SouthAustralia.

HotWeatherCan Be Dangerous

Doctorssaypeoplecandomanythings to protectthemselves from the dangers of extremeheat. Stay out of the sun, ifpossible. Drinklots of coolwater. Wearlight-coloredclothing and hatsmade of naturalmaterials. Makesure the clothing is loose, permittingfreedom of movement. Also, learn the dangersigns of the medicalproblemslinked to heat.The mostcommonhealthproblemlinked to hotweather is heatstress. Usually, it is also the leastsevere.

Mostpeoplesufferonlymusclepainbecause of heatstress. The pain is a warning that the body is becomingtoohot. Doctorssaythosesufferingmusclepainshouldstopallactivity and rest in a coolplace. Theyshouldalsodrinkcoolliquids. Doctorssay not to return to physicalactivity for a fewhoursbecauseseriousconditionscandevelop.

Hotweather is dangerous for peoplewhoweightoomuch and havetoomuchbodyfat, and for peoplewhodrinkalcohol. It alsoincreasesdangers for peoplewhomusttakemedicine for highbloodpressure, poorbloodcirculation, nervousness or depression.

Untreatedheatstresscanlead to a moreseriousproblemcalledheatexhaustion. A personsuffering from heatexhaustionlosestoomuchwaterthroughperspiration. He or she will feelweak and extremelytired. Theymayhavetroublewalkingnormally. Heatexhaustionmayalsoproduce a fastheartbeat, breathingproblems and pain in the head, chest or stomach. Doctorssaypeoplewithsuchproblemsshouldrestquietly in a coolplace and drinkplenty of water. Theyalsosay it mayhelp to washwithcoolwater.

Drink a Lot of Water

Expertssayeven a twopercentdrop in the body's watersupplymaycausesigns of dehydration. Thesesignsincludeproblemswithmemory and evensimplemathematics. The treatment for dehydrationexhaustion is the same as for heatexhaustion. Drinkplenty of water and rest in a coolplace. Evenbetter, doctorssay, drinkabouttwoliters of water a daysoproblemswithdehydration will not have a chance to develop.

Heatexhaustioncanlead to heatstrokeif it is not treated. Heatstroke is the mostseriousdisorderlinked to hotweather. It resultswhen the body is not able to control its temperature. The bodytemperatureincreases and perspirationfails.

Generally, the bodytemperaturerises to morethan 40 degreesCelsius. The bodystopsperspiring. The skinbecomesdry and veryhot. A personmaybecomeunconscious, not knowingwhat is happening.

Doctorssaytissues and organsbegin to cookwhen the body's temperature is higherthan 42 degreesCelsius. Permanentbraindamage and deathmayresult. Someonesufferingheatstrokerequiresimmediatemedicalattention. Doctorssaysuchtreatment is necessary or the personcoulddiebeforehelparrives.

The purpose of immediatetreatment is to cool the victim as quickly as possible to stop the temperature from increasing. Begin by moving the victim out of the sun. Raise the person’s feetupaboutthirtycentimeters. Take off the victim’s clothing. Putcoolwater on the body. Placepieces of ice in areaswherebloodpassageways are close to the skin. Theseinclude the back of the neck and under the arms.

Expertssay it is important to know the dangersigns of the medicaldisorderslinked to hotweather. It is alsoimportant to knowwhat to doif the signsappear in yourself or in someoneelse.

Expertssaywater is important for manyreasons. Between 55 and 75 percent of the body is water. Water in bloodcarrieshormones and antibodiesthroughout the body. Water in urinecarriesawaywastematerials. Water is needed for cooling the body on hotdays, and when we are working or exercising. Watercarriesbodyheat to the surface of the skin. There, the heat is lostthroughperspiration.

Healthexpertssayadultsshoulddrinkabouttwoliters of water a day to replaceall the waterlost in liquidwaste and perspiration. Theysaypeopleshoulddrinkmorethan that in hotweather.

Expertssay it is important to drinkbefore, during and afterexercise. Theysay we shoulddrinkwaterevenbefore we start to feellike we needsomething to drink. Duringhotweather, coolliquids are best. Also, avoidsweetdrinks and alcohol.

TooMuchWaterMayCauseHarm

We need to add that doctorsalsosay it is possible to drinktoomuchwater. Somepeople, for example, do this iftheyexercisehardduring a heatwave. Expertswith the MayoClinicsaydrinkingtoomuchwatercancausehyponatremia. In this condition, the level of sodium in the bloodfallstoolow.

The result is that the amount of water in the bodyincreases. This causescells to becomelarger. MayoClinicexpertssay the enlargedcellscancause a person to becomesick or restless. Theyalsocaninterferewithmentalability, makemusclesweak and causepain in the head. In a mildcase, simplyreducingfluidsmay be all that the personneeds. But medicalhelp is necessaryif the condition is moresevere.

Expertshavesuggestions for runners and othersexercising or workinghard in hotweather. Theysaydrinking a sportsdrinkwithsodium in it canhelpprevent the condition.

Doctorssayactionsotherthandrinkingwatercanprotectagainst the healthdangers of heat. Stay out of the sun, ifpossible. Wearloose, lightweight and lightcoloredclothes. Wear a hat or otherheadcoveringwhen in the sun. Eatfewerhot and heavyfoods. Ifpossible, cookfoodsduringcoolertimes of the day. Also, restmoreoften. Physicalactivityproducesbodyheat.

Expertssaythesesimplestepscanprevent the healthproblemslinked to heat. They will preventsickness, helpyoufeelbetter and mayevensaveyourlife.

This Science in the News was written by MilagrosArdin. Ourproducer was JuneSimms. I’m BobDoughty.